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Introduction Multimedia definitions:- –Multi means many; much; multiple –Medium means: a substance regarded as the means of transmission of a force or effect; a channel or system of communication, information or entertainment –Medium means: an intervening substance through which something is transmitted or carried on. –So Multimedia is medium having multiple content forms.

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Introduction Multimedia can have many definitions these include: Multimedia means that computer information can be represented through audio, video, and animation in addition to traditional media (i.e., text, graphic drawings, images). A good general definition is: Multimedia is the field concerned with the computer- controlled integration of text, graphics, drawings, still and moving images (Video), animation, sound, audio, and any other media where every type of information can be represented, stored, transmitted and processed digitally. Multimedia is woven combinations of text, graphic art, sound, animation, video and other kinds of elements.

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Introduction Multimedia includes a combination of text, audio, still images, animation, video, and interactivity content forms. Multimedia is usually recorded & played, displayed or accessed by computerized and electronic devices, but can also be part of a live performance. Multimedia also describes electronic media devices used to store and experience multimedia content.

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Multimedia Project and Title The software vehicle, the messages and the content presented on a computer or television screen together is called a multimedia project. If the project will be shipped or sold to the consumer or end users, typically in a box or sleeve with or without instructions it is said to be a multimedia title.

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Multimedia and Interactivity Multimedia is interactive when the end-user is allowed to control what and when the elements are delivered. Interactive Multimedia is Hypermedia, when the end-user is provided with the structure of linked elements through which he/she can navigate.

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Multimedia and Interactivity Multimedia is linear, when it is not interactive and the users just sit and watch as if it is a movie, e.g., cinema presentation Multimedia is nonlinear, when the users are given the navigational control and can browse the contents at will, e.g., computer game, computer-based training.

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Hypertext is a text which contains links to other texts. The term was invented by Ted Nelson around Hypertext is therefore usually non-linear. HyperMedia is not constrained to be text-based. It can include other media, e.g., graphics, images, and especially the continuous media – sound and video. When you provide a structure of linked elements through which the user can navigate, interactive multimedia becomes hypermedia. Apparently, Ted Nelson was also the first to use this term. The World Wide Web (WWW) is the best example of hypermedia applications. Hypertext and Hyper Media

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Multimedia Authoring Tools Multimedia elements are composed into a project using authoring tools. Multimedia Authoring tools are those programs that provide the capability for creating a complete multimedia presentations by linking together objects such as a paragraph of text, an illustration, an audio, with appropriate interactive user control

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By defining the objects' relationships to each other, and by sequencing them in an appropriate order, authors (who use authoring tools) can produce attractive and useful graphical applications. To name a few authoring tools –Macromedia Flash –Macromedia Director –Authorware The hardware and the software that govern the limits of what can happen are multimedia platform or environment Multimedia Authoring Tools

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Multimedia System A Multimedia System is a system capable of processing multimedia data and applications. A Multimedia System is characterised by the processing, storage, generation, manipulation and rendition of Multimedia information.

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A Multimedia system has four basic characteristics: –Multimedia systems must be computer controlled. –Multimedia systems are integrated. –The information they handle must be represented digitally. –The interface to the final presentation of media is usually interactive. Characteristics of Multimedia System

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Challenges for Multimedia System Supporting multimedia applications over a computer network renders the application distributed. Multimedia systems should be a real time system The system should take care of: Sequencing within the media - playing frames in correct order/time frame in video Synchronisation - inter-media scheduling (e.g. Video and Audio).

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Challenges for Multimedia Systems The key issues that multimedia systems need to deal with are: –How to represent and store temporal information. –How to strictly maintain the temporal relationships on play back/retrieval –Data has to be represented digitally –Data compression techniques

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Desirable Features Given the challenges the following features are desirable for a Multimedia System: –Very High Processing Power –Multimedia Capable File System e.g. RAID technology. –Data Representations/File Formats that support multimedia Compression/decompression in real-time. –Efficient and High I/O Needs to allow for real-time recording as well as playback of data. e.g. Direct to Disk recording systems.

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Desirable Features –Storage and Memory large storage units (of the order of Gb or more) and large memory ( Mb or more). Large Caches also required and frequently of Level 2 and 3 hierarchy for efficient management. –Network Support Client-server systems / distributed systems common –Software Tools user friendly tools needed to handle media, design and develop applications, deliver media